Graft versus host disease (GVHD) remains the most significant complication of allogeneic hematopoietic stem cell transplantation (HCT). While the use of HCT has grown significantly safer and has demonstrated broad efficacy in the setting of a broad range of blood diseases, immunosuppressive therapy has not dramatically evolved since the introduction of calcineurin inhibitor-based approaches decades ago. The availability
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GVHD remains a critical problem and major barrier to the more widespread utilization of HCT, especially for nonmalignant diseases, where tolerance of treatment-related mortality is understandably low.

There is a compelling need for novel immunosuppressive agents that can effectively limit alloreactivity mediated by donor T and B cells, while relatively sparing pathogen-specific T cells, including those mediating antiviral T cell responses important in the post-HCT interval.

In the past decade, drug development has facilitated the introduction into preclinical and clinical trials of a broad range of agents that in addition to targeting pathways of interest in target cells (e.g., aberrant signaling in cancer cells) may also effectively inhibit T and/or B cell responses. Examples include hypomethylating agents (e.g., azacitidine), HDAC inhibitors (e.g., vorinostat), MEK inhibitors (e.g., trametinib) and BTK inhibitors (e.g., ibrutinib). Each of these classes of agents has been demonstrated in preclinical and/or clinical studies to also limit alloreactive T cells, and/or augment regulatory T cell responses, leading to a net reduction of alloreactivity. Unlike traditional agents (e.g., the calcineurin inhibitors) these agents appear to be more selective, and in some cases may have dual benefit in reducing relapse.

The NHLBI can facilitate the identification and translation to clinical practice in the setting of HCT trials of novel immunosuppressive agents.

Feasibility and challenges of addressing this CQ or CC:

Research funding targeted to improving the pipeline of novel immunosuppressive agents could have immediate and dramatic impact in the field of HCT, especially impacting its application for nonmalignant diseases. Patients lacking optimal registry donors, especially those from underrepresented minority groups, will particularly benefit from improvements in immunosuppression, as patients receiving less than optimally matched donors are at much higher risk of GVHD.

The NHLBI can encourage and facilitate research that tests compounds that have already passed through the drug development process, but in many cases were not intended to function as immunosuppressive agents. Compelling preclinical studies have suggested that targeted inhibition of T and B cells, and/or epigenetic modifiers can lessen alloreactivity while preserving beneficial cellular immune responses and facilitating immune reconstitution.

It will be far easier to appropriate therapeutic agents already developed for another purpose than to do novel drug development from scratch. In many cases, preclinical studies have highlighted the therapeutic potential in immunosuppression for agents that have been developed to treat malignancies, but yielded suboptimal success. Research that encourages the development of these drugs as part of a combined immunosuppressive/immunomodulation approach may rescue such compounds, while yielding potential dramatic advances in clinical HCT.

Name of idea submitter and other team members who worked on this idea:
Krishna Komanduri, M.D.

HCT is associated with high rates of morbidity and mortality from transplant-related complications. Reduction in transplant-related mortality would lead to more favorable risk/benefit assessments for the ability of transplant to cure life-threatening hematologic disorders including non-malignant conditions. Comorbidity and patient-reported functional status impairment are known to increase the risk for transplant-related mortality. Single institution studies suggest that cardiorespiratory fitness may serve a similar role as a predictive pre-transplant variable. Unlike comorbidity, cardiorespiratory fitness is potentially modifiable. However, the optimal way to improve cardiorespiratory fitness through pre-transplant exercise and lifestyle interventions is not known. Understanding how to improve cardiorespiratory fitness through a short term intervention would also benefit other health conditions relevant to the NHLBI in which future treatment is intensive and associated with significant risk.

Feasibility and challenges of addressing this CQ or CC:

Understanding how to improve cardiorespiratory fitness in a short period of time will require a research agenda that addresses the following challenges: how to measure cardiorespiratory fitness in a generalized and scalable way, which may or may not require maximal exercise testing for all participants; how to design intensive exercise interventions that are at least partially home-based, in order to minimize resource burden on patients and centers; and how to personalize intervention delivery and testing in a way that is tailored to the baseline fitness levels and capabilities of each participant. Meeting these challenges will enable large-scale, personalized exercise testing and intervention delivery in other non-transplant populations.

Name of idea submitter and other team members who worked on this idea:
William Wood, Thomas Shea

Voting

Do modifications in the recipient gut or lung microbiome affect development of tolerance and immunologic recovery after allogeneic hematopoietic stem cell transplantation (HCT) and can re-institution of a more normal microbiome lead to improved outcomes?

HCT leads to profound changes in the host microbiome. Some small studies indicate that differential recovery of the gut microbiome is associated with differential outcomes, including graft-versus-host disease and mortality. Less is known about the pulmonary microbiome. Better understanding of the role of the microbiome in facilitating posttransplant recovery could lead to easily administered interventions and provide important insights into the role of different subpopulations of the microbiome on the health of all people.

Feasibility and challenges of addressing this CQ or CC:

Preclinical and clinical studies of this area would be greatly facilitated by a microbiome repository linked to high quality clinical data and would provide opportunity for insight into the role of the microbiome in health and disease.

Name of idea submitter and other team members who worked on this idea:
Mary Horowitz

Voting

What are the best inroads for the NHLBI to support innovative approaches in the next 5-10 years, especially blood cell therapies based on hematopoietic stem cell and novel gene therapy approaches to control or even cure HIV infection?

HIV control or possibly even HIV cure could result from developing novel cell therapies, especially hematopoietic stem cell (HSC) transplants, and might also result from early use of antiretroviral therapy in acutely HIV-infected individuals.

• Transplantation of HSC including engineered cells has the potential to eradicate HIV reservoirs for HIV cure: the Berlin patient treated with HSC transplant remains free of HIV and is still the only patient cured of HIV infection as of today;

• Identification of acute HIV infections through routine blood donor screening and early anti-retroviral therapy for identified HIV-infected donors can limit or even prevent the establishment of HIV reservoirs.

Feasibility and challenges of addressing this CQ or CC:

• The Berlin patient has provided the proof of concept that HIV infection can be eradicated, that is, sterilizing cure can be achieved, through HSC transplantation in combination with other therapies;

• Recent studies have shown that early identification of HIV infection and treatment of infected individuals with anti-retroviral therapy as soon as possible can significantly limit the size of the HIV reservoirs even if such early treatment may not be able to completely prevent the establishment of HIV reservoirs; routine blood donor screening for both anti-HIV antibodies and HIV RNA among blood donors offers unique opportunities to identify acute HIV infections.

For HIV cure, the challenges include:

• Generation of HIV-resistant HSCs in adequate quantity for transplantation;

• Efficiency of homing and expansion of HIV-resistant HSC transplants;

• Efficiency in replacing HIV-infected cells, including CD4+ resting cells as the major HIV reservoirs, with HIV-resistant HSCs following transplantation;

Voting

Advances in the care of pediatric patients with sickle cell disease ( SCD) have resulted in improved survival to adulthood.However, adulthood is marked by rapid disease progression, impaired quality of life and premature mortality. Hematopoietic cell transplantation(HCT) from matched sibling donor has curative potential, but has been offered mainly to children. Refinements in the conditioning regimen, supportive care,
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To overcome this obstacle to progress in the field, we propose the creation of the funding mechanisms for a multicenter clinical trial consortium which would bring together investigators in field and facilitate study the outcomes of CT for patients with different types of donors and stem cell sources and compare them to outcomes in phenotypically matched controls receiving best available standard of care.Answering the compelling question about the role of CT in the management of SCD has the potential to have a catalytic effect in progress in this field. Patients are are then more likely to receive CT or standard of care at the appropriate time and in the manner in which they are most likely to have a positive outcome. This has the potential to reduce morbidity and premature mortality and in the long run, to decrease the burden of the disease on the healthcare system. The advent of clinical trials of gene therapies for SCD offers the prospect of even greater applicability of curative therapies. Thus, a consortium developed to answer this CQ would serve as a crucial vehicle for providing access to a greater proportion of patient to these personalized curative therapies . Such studies would also be powered to answer the question about who should receive the curative therapy, when they should receive it, and how it would impact their SCD related complications, late effects, survival and quality of life and help families make informed choice appropriate for their situation.

Feasibility and challenges of addressing this CQ or CC:

The increasing applicability and acceptability of HCT for SCD is evidenced by the doubling in the number of such procedures reported to CIBMTR in the decade starting 2001. Refinements in conditioning regimen and supportive care continue to improve outcomes in children and now in adults with SCD undergoing HCT from HLA matched related donors. Recently, HCT from unrelated donors and from haplo-identical donors have further increased the applicability of HCT. Opening of gene therapy trials has further raised the prospect of cure for a greater proportion of patients. These developments are evidence of the feasibility of recruitment to large multi-center comparative trials of SCD and standard of care. Recently, there has been increasing collaboration among investigators in the field with informal consortia being developed by investigators coming together to study HCT for children, adults or HCT from haplo-identical donors. These groups are also increasingly working with SCD hematologists, families and other stakeholders. There is also increasing cross-cutting collaborations with other medical specialists and behavioral and translational scientists Thus, the convergence of several factors described above suggests that the time is fortuitous for a major initiative from the NHLBI to bring investigators together and create the infrastructure that will enable these investigators to seek definitive answers to the challenging question “What is the place of curative therapy in SCD?”.

Name of idea submitter and other team members who worked on this idea:
Lakshmanan Krishnamurti, MD, Allistair Abraham MD, John Horan MD and members of the Sickle cell Transplantation and Research Alliance

In Acute Graft Versus Host Disease (aGVHD), we would like to examine whether early and intensified delivery of ECP as part of standard prophylaxis will decrease overall corticosteroid exposure while preserving expected relapse rates in patients undergoing unrelated donor hematopoietic stem cell transplantation (HSCT).
Chronic GVHD (cGVHD) is common after HSCT (30-50% recipients) and is a major contributor to late transplant-related
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Patients who develop aGVHD undergo toxic therapy with high-dose corticosteroids, often for long durations, resulting in high morbidity and treatment related mortality. Alternatively, T cell depletion of the donor graft to reduce GVHD is associated with high rates of infection and relapse of the disease that led to the HSCT. Targeting other pathways of GVHD pathogenesis may preserve the beneficial immune reconstitution and graft-versus-tumor (GVT) effects, while ameliorating the severity of GVHD. One such pathway involves regulatory T cells (T regs), which inhibit T cell alloreactivity, and are correlated with the incidence and severity of GVHD without loss of GVT. To date, there is no consensus on a standard second-line therapy for aGVHD, and current approaches focus mainly on intensification of immunosuppression. Addressing this compelling question will help to decrease overall corticosteroid exposure while preserving the expected relapse rates in patients undergoing unrelated donor HSCT.

Appropriate initial therapy for cGVHD involves high doses & prolonged use (yrs) of corticosteroids, while patients still develop irreversible sclerotic manifestations of disease. Early intervention prior to disease onset may help prevent cGVHD development or lessen its severity, requiring less corticosteroid exposure. Addressing the compelling question for cGVHD will help decrease exposure to drugs with associated morbidity, while preserving expected relapse rates in these patients.

Feasibility and challenges of addressing this CQ or CC:

Feasibility:

* GVHD has relatively high incidence after HSCT and at the same time there is a lack of consensus on standard second line therapy for the disease. Thus, there will be increased interest in developing and participation in those studies.

** ECP is generally well tolerated and complications are infrequent.

*** There is a great potential for multi-discipline collaboration approach in this patients’ population.

*** There is an opportunity to engage industry partners in the design and support for these studies.

**** There are numerous scientific opportunities for meritorious science as there have been limited systematic studies of ECP mechanisms of as well as standardization of apheresis protocols based on GVHD disease state.

Challenges:

* Limited number of institutions providing ECP treatment.

** Cost of the procedures (although Centers for Medicare and Medicaid Services now covers ECP for cGVHD).

*** There is a very limited number of animal models available for apheresis research in general, and studies of the mechanism(s) of action of photopheresis have been very limited as well as difficult and expensive to perform. However understanding pathological mechanisms and its relationship to response to apheresis is critical for optimization and advancement of patient care.

****Lack of infra-structure for apheresis research.

Name of idea submitter and other team members who worked on this idea:
Joseph Schwartz on behalf of ASFA

To extend our knowledge of the pathobiology of heart, lung, blood, and sleep disorders and enable clinical investigations that advance the prediction, prevention, preemption, treatment, and cures of human disease.